The present invention relates generally to an implement of a work machine, and more particularly to a protection assembly for the base and cutting edge assemblies of an implement of a work machine.
A work machine, such as an excavator, may include an implement such as a bucket for moving, excavating, or grading dirt or other types of material. The shape of the bucket, especially its base edge, contributes to the effectiveness of the work machine in performing these tasks.
A straight base edge of the bucket is generally preferred for moving loose materials so that the base edge can scrape material close to an underlying surface without causing damage to the underlying surface. For example, a pile of gravel that is to be moved may lie upon packed soil or asphalt. In addition, the straight base edge may perform adequately for excavating in some situations.
In many instances it is desirable to attach a cutting edge to the base edge to protect the base edge from wear, thus extending it""s life. The base and cutting edge combination function in essentially the same manner as a bucket having only a base edge and is intended for loading loose material and not necessarily for the excavation of material.
By contrast, a bucket having a toothed base edge is generally preferred when excavating, especially in hard-packed virgin soil. The toothed base edge is better suited for penetrating the hard-packed soil. Moreover, the teeth may be provided sufficient strength to minimize damage during excavating, whereas a straight base edge tends to wear and bend.
So it can be seen that a single bucket will not necessarily be appropriate for all applications. The bucket having teeth will out perform the bucket having a base edge or base edge/cutting edge combination in excavation applications while the bucket having just a base edge or base edge/cutting edge combination, will be preferred during loading applications.
In order to alleviate the need for having two separate buckets to perform efficiently, it has been known to attach a tooth bar over the base edge of a bucket to temporarily provide that bucket with teeth for excavation. Typically, a tooth bar can be attached to the sides of a bucket by a pair of bolts and may be easily removed or attached depending on the type of work.
Individually mounting teeth to the base edge is generally known. However, exposed portions of the base edge are still subject to wear and damage. In addition, mounting and removing each tooth from the bucket requires a significant amount of time.
In some instances, tooth bars are used that surround and protect just the base edge of the bucket. Teeth are attached at intervals along the tooth bar to form a tooth bar assembly.
Conventionally, tooth bars must substantially contact the base edge along the length of the base edge in order to transfer the loads encountered and thus to avoid damaging the tooth bar, its attachments to the bucket, or the base edge. A slotted hole in mounting brackets of the tooth bar assembly allows for adjusting the position of the tooth bar assembly to achieve this contact. A bolted connection through a hole in the bucket and the slotted hole in the mounting bracket is used to maintain this positioning.
While it is typical to use a bolted connection to attach the tooth bar assembly to the bucket, it may be preferable to use a pinned connection in some instances. A pinned connection may utilize a pin having a diameter that may carry a larger load than a bolt and may decrease the installation time required by bolted connections.
The present invention is directed to overcoming one or more of the problems or disadvantages associated with the prior art.
While the invention will be described in connection with certain embodiments, it will be understood that the invention is not limited to these embodiments. On the contrary, the invention includes all alternatives, modifications and equivalents as may be included within the spirit and scope of the present invention.
In accordance with the principles of the present invention, there is provided a protection assembly for protecting the base edge and an attached cutting edge of a bucket or other implement of a work machine. The bucket has a pair of upright side walls and a bottom wall that extends therebetween and terminates in a base edge subject to wear. The cutting edge is attached to an underside of the bucket bottom wall adjacent the base edge. In accordance with one aspect of the present invention, the protection assembly includes a digging plate adapted to be positioned adjacent an underside of the cutting edge and a cover plate operatively connected to the digging plate to form an elongated edge recess that is adapted to receive the base and cutting edges of the bucket. A plurality of teeth are forwardly disposed along the digging plate.
A pair of spaced apart mounting brackets are positioned adjacent opposite ends of the elongated edge recess and are configured to reside within the upright side walls of the bucket. Each mounting bracket has a mounting aperture, such as an elongated slot, that is adapted to register with a mounting aperture formed in each of the bucket side walls. Fasteners extend through the mounting apertures formed in the bucket side walls and mounting brackets to secure the protection assembly to the bucket. Locking members may be provided to prevent fore and aft movement of the protection assembly relative to the bucket.
In accordance with another aspect of the present invention, a pair of spaced apart elongated lug members are operatively connected to the bucket bottom wall and extend forwardly from the base edge. A pair of spaced apart recesses are formed in the cover plate for receiving and engaging forwardly extending portions of the lug members to position the edge recess relative to the base edge of the bucket when the protection assembly is attached to the bucket.
The protection assembly further includes a pair of spaced apart retaining members operatively connected to at least one of the digging plate and the cover plate for forming rearwardly facing throats with the recesses formed in the cover plate. The rearwardly facing throats are adapted to receive the forwardly extending portions of the lug members. When the forward portions of the lug members are inserted into the rearwardly facing throats, and the fasteners are inserted to secure the mounting brackets to the bucket side walls, the protection assembly is consistently positioned at the same location on the bucket regardless of the amount of wear on the base edge or cutting edge.